A bipartisan group of five senators and two representatives wrote to the FDA last month, urging the agency to promptly change hydrocodone painkillers such as Vicodin from Schedule III to Schedule II drugs. To do this, the Drug Enforcement Administration must receive public comment after publishing information about the change in the Federal Register, the FDA said in a March 5 response letter that has been obtained by The Hill. Regulations also require the FDA to conduct further research as part of the reclassifying process, the letter said.

The reclassification, recommended in January by an FDA advisory panel, would make it more difficult to obtain these commonly prescribed medications.

Lawmakers say hydrocodone is fueling a nationwide epidemic of prescription painkiller addiction, but critics say reclassification will make it unnecessarily hard for nursing homes and other healthcare providers to care for those in pain.

The fastest potential route to reclassification would be Congressional legislation mandating the change, the FDA said. A House staffer told The Hill such a bill is pending, but noted 14 years have already passed since Congress first asked the FDA to reclassify hydrocodone.